bubble_sort.rb

def bubble_sort to_sort
  last = to_sort.length - 1

  loop do
    sorted = true

    for i in (0...last)
      if to_sort[i] > to_sort[i + 1]
        to_sort[i], to_sort[i + 1] = to_sort[i + 1], to_sort[i]
        sorted = false
      end
    end

    last -= 1

    break if sorted
  end

  to_sort
end

p(bubble_sort([4, 3, 78, 2, 0, 2]) == [0, 2, 2, 3, 4, 78])
p(bubble_sort([1, 2, 3, 4, 5]) == [1, 2, 3, 4, 5])
p(bubble_sort([5, 4, 3, 2, 1]) == [1, 2, 3, 4, 5])
p(bubble_sort([5, -84, 42, 15, 0, 2, 2, 67]) == [-84, 0, 2, 2, 5, 15, 42, 67])


def bubble_sort_by to_sort
  last = to_sort.length - 1

  loop do
    sorted = true

    for i in (0...last)
      if (yield(to_sort[i], to_sort[i + 1]) > 0)
        to_sort[i], to_sort[i + 1] = to_sort[i + 1], to_sort[i]
        sorted = false
      end
    end

    last -= 1

    break if sorted
  end

  to_sort
end

p(bubble_sort_by(['hi','hello','hey']) do |left, right|
  left.length - right.length
end == ['hi', 'hey', 'hello'])

p(bubble_sort_by([5, 3, 7, 1]) do |left, right|
  left - right
end == [1, 3, 5, 7])

p(bubble_sort_by([5, 3, 7, 1]) do |left, right|
  right - left
end == [7, 5, 3, 1])

p(bubble_sort_by(['hey', 'my', 'name', 'is', 'Niko']) do |left, right|
  left <=> right
end == ['Niko', 'hey', 'is', 'my', 'name'])

p(bubble_sort_by(['hey', 'my', 'name', 'is', 'Niko']) do |left, right|
  right <=> left
end == ['name', 'my', 'is', 'hey', 'Niko'])